Lens Turbo II on full frame

[caspert79]

Not so long ago I saw a picture on Flickr, according to the description made with a Samyang 85/1.4 on a Lens Turbo II, attached to a Sony A7something. Result was an image equivalent to approximately 62mm f/1. I tried to contact the photographer, but no response.
Does anybody know if this is actually possible? Can a Lens Turbo II project a larger than full frame image circle onto a full frame sensor? If nobody knows I'm probably willing to buy one and try it out.

[calvin83]

I doubt the Lens Turbo II can project an image cover 35mm full frame without dark corners.

[caspert79]

Found the image of interest:
https://flic.kr/p/2eSgGaJ

[calvin83]

2048/1490~=1.37 which is not the native aspect ratio 3/2=1.5 .

[caspert79]

[calvin83]

The image circle will be at least ~23.5mmx23.5mm on the version II. The rest are bonus.

[eggplant]

Not the Lens Turbo II, but ProfHankD in 2015 tested what appears to be the original Zhongyi Lens Turbo on full frame https://www.dpreview.com/forums/thread/3699113

He sadly never tested any longer focal length lenses.

[caspert79]

[Pancolart]

Interesting. I'd love to see my Samyang 1.4/35mm tested.

[DConvert]

It wasn't simply using the A7 in crop mode?

[caspert79]

[calvin83]

I won't consider using a focal reducer + full frame camera. A better solution will be a GFX 50 or 100.

[caspert79]

[calvin83]

[DConvert]

[calvin83]

[philslizzy]

they crop badly, unless you want that, you achieve nothing apart from a stop of seed

[visualopsins]

[ZuikosHexanonsandVivitars]

Not sure if I got this right, but to me it sounds like "gain some, lose some". Essentially, reducing the 85mm lens to 60mm with a lens turbo creates a brighter image on the sensor in the first place. But in the same way, the full frame sensor is effectively reduced to something like the size of APS-C because the slimmer cone of light from the lens turbo doesn´t cover the sensor fully anymore (as discussed above). Thus you require the one stop you won in the first step, to achieve the same DOF on the smaller remaining sensor surface.

So probably, a similar result could have been achieved with some 55mm f1.2 Zuiko or 57mm f1.2 Hexanon (or else comparable), but still retaining the benefit of the full resolution of the sensor.

On the other hand, I admire the creative idea to crank those things together and get a beautiful pic out of it, so why not?

[cbass]

[DConvert]

[kathala]

I am using the LT II with the Canon 85/1.2 in FF mode on 7r2. There is a bit of vignette, which is almost entirely the fault of the reducer, not the lens (the lens covers GFX, which is however smaller than a resulting FF x .7 sensor would be).
You still gain quite a bit of additional angle of view, though! Paired with the separation, which of course stays the same, you indeed get something like a 6o mm f/o.something.

Allegedly, the Metabones covers slightly more. I tested one with a Sigma 85/1.4 once, and the difference was there, but small.

If you're interested, my list shows which lenses cover GFX or FF + reducer to what extent: https://docs.google.com/spreadsheets/d/1uxvvpxJ9QVFFyh0pW2rs9KBmUW9vlh-d-VnbcLDCTn8/edit?usp=share_link

If you work in a non-full frame format (1:1, 1:3 etc), this is a very viable option!


Using MF lenses is less relevant, since none match the speed of FF - even a fast 8o mm MF only equals a FF 5o/1.4ish
This holds true even on GFX - you CAN adapt an 8o/2 MF lens (IF you find the right reducer, indeed). Or you can have an 85/1.2 or 1.4 which covers the full GFX format.

[visualopsins]

Here we go for GFX users with a collection of Medium Format lenses!: https://kipon.com/kipon-start-to-accept-preorder-for-m645-gfx-e-electronic-adapters/

[caspert79]

[Pancolart]